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The Relationship between Teacher Attrition and Student Achievement in Reading among Middle School Students
The purpose of this study was to determine whether a significant relationship existed between teacher attrition and student success in middle school reading by conducting a quantitative analysis. Additionally, the inclusion of school demographic characteristics were included in the model to consider previous findings referencing the challenges schools face in attracting and retaining teachers in low performing urban schools with high populations of economically disadvantaged and minority students. In this analysis, the relationship between teacher attrition and student achievement in middle school as measured by the State of Texas Assessments of Academic Readiness (STAAR) for reading among middle school students in Grades 6, 7, and 8, as reported on the Texas Academic Performance Reports (TAPR), were examined. The regression models used to analyze the three research questions addressed in the study include an examination of teacher attrition on campus pass rates, and grade level pass rates for sixth, seventh, and eighth grades as measured by the STAAR Reading assessment. The data utilized in this study were collected from seven North Texas middle schools in a fast growth school district together with their comparable campuses as identified by the Texas Education Agency for the school years 2013-2014 through 2015-2016. The results of the analysis indicate teacher attrition accounts for a significant variance in STAAR Reading pass rates among middle school students. Additionally, the school demographic characteristics defined as percentage economically disadvantaged, percentage English language learners, mobility rates, and percentage white students account for 83.4% of the variance in the average campus pass rates for STAAR Reading when combined.
Kinetic Study of the Reactions of Chlorine Atoms with Fluoromethane and Fluoromethane-d3 in the Gas Phase
The kinetics of the gas-phase reactions of chlorine atoms with fluoromethane (CH3F) and fluoromethane-d3(CD3F) were tested experimentally. The relative rate method was applied by using CH4 as the reference compound for fluoromethane (CH3F) and CH4 and CH3F as the reference compound for fluoromethane-d3(CD3F). The rate constants for H-abstraction from CH3F and D-abstraction from CD3F were measured at room temperature and a total pressure of 920 Torr using Ar as a diluent. The rate constants are described by the expressions: kH= (3.50±0.52) x 10-13 cm3 molecule-1 s-1 and kD=(5.0±0.51) x 10-14 cm3 molecule-1 s-1. The kinetic isotope effect, equal to the ratio kH/kD, was found to be 7.0±1.2 at room temperature.
Development and Analysis of a Mobile Node Tracking Antenna Control System
A wireless communication system allows two parties to exchange information over long distances. The antenna is the component of a wireless communication system that allows information to be converted into electromagnetic radiation that propagates through the air. A system using an antenna with a highly directional beam pattern allows for high power transmission and reception of data. For a directional antenna to serve its purpose, it must be accurately pointed at the object it is communicating with. To communicate with a mobile node, knowledge of the mobile node's position must be gained so the directional antenna can be regularly pointed toward the moving target. The Global Positioning System (GPS) provides an accurate source of three-dimensional position information for the mobile node. This thesis develops an antenna control station that uses GPS information to track a mobile node and point a directional antenna toward the mobile node. Analysis of the subsystems used and integrated system test results are provided to assess the viability of the antenna control station.
The Impact of Commuting on Mental Health
The purpose of this research is to explicate the relationship between commuting behavior, stress, and mental health. The overall results from the regression analysis turned out to be inconclusive given the researcher's initial hypothesis. The commute time reported by respondents did not have a statistically significant bearing on mental health outcomes. This was true for both the normal sample, and the sample that was split by gender.
MBE Growth and Characterization of Graphene on Well-Defined Cobalt Oxide Surfaces: Graphene Spintronics without Spin Injection
The direct growth of graphene by scalable methods on magnetic insulators is important for industrial development of graphene-based spintronic devices, and a route towards substrate-induced spin polarization in graphene without spin injection. X-ray photoelectron spectroscopy (XPS), low energy electron diffraction LEED, electron energy loss spectroscopy (EELS) and Auger electron spectroscopy (AES) demonstrate the growth of Co3O4(111) and CoO(111) to thicknesses greater than 100 Å on Ru(0001) surfaces, by molecular beam epitaxy (MBE). The results obtained show that the formation of the different cobalt oxide phases is O2 partial pressure dependent under same temperature and vacuum conditions and that the films are stoichiometric. Electrical I-V measurement of the Co3O4(111) show characteristic hysteresis indicative of resistive switching and thus suitable for advanced device applications. In addition, the growth of Co0.5Fe0.5O(111) was also achieved by MBE and these films were observed to be OH-stabilized. C MBE yielded azimuthally oriented few layer graphene on the OH-terminated CoO(111), Co0.5Fe0.5O(111) and Co3O4(111). AES confirms the growth of (111)-ordered sp2 C layers. EELS data demonstrate significant graphene-to-oxide charge transfer with Raman spectroscopy showing the formation of a graphene-oxide buffer layer, in excellent agreement with previous theoretical predictions. XPS data show the formation of C-O covalent bonding between the oxide layer and the first monolayer (ML) of C. LEED data reveal that the graphene overlayers on all substrates exhibit C3V. The reduction of graphene symmetry to C3V – correlated with C-O bond formation – enables spin-orbit coupling in graphene. Consequences may include a significant band gap and room temperature spin Hall effect – important for spintronic device applications. The results suggest a general pattern of graphene/graphene oxide growth and symmetry lowering for graphene formation on the (111) surfaces of rocksalt-structured oxides.
Assessment of Competencies among Doctoral Trainees in Psychology
The recent shift to a culture of competence has permeated several areas of professional psychology, including competency identification, competency-based education training, and competency assessment. A competency framework has also been applied to various programs and specialty areas within psychology, such as clinical, counseling, clinical health, school, cultural diversity, neuro-, gero-, child, and pediatric psychology. Despite the spread of competency focus throughout psychology, few standardized measures of competency assessment have been developed. To the authors' knowledge, only four published studies on measures of competency assessment in psychology currently exist. While these measures demonstrate significant steps in progressing the assessment of confidence, three of these measures were designed for use with individual programs, two of these international (i.e., UK and Taiwan). The current study applied the seminal Competency Benchmarks, via a recently adapted benchmarks form (i.e., Practicum Evaluation form; PEF), to practicum students at the University of North Texas. In addition to traditional supervisor ratings, the present study also involved self-, peer supervisor, and peer supervisee ratings to provide 360-degree evaluations. Item-response theory (IRT) was used to evaluate the psychometric properties of the PEF and inform potential revisions of this form. Supervisor ratings of competency were found to fit the Rasch model specified, lending support to use of the benchmarks framework as assessed by this form. Self- and peer-ratings were significantly correlated with supervisor ratings, indicating that there may be some utility to 360-degree evaluations. Finally, as predicted, foundational competencies were rated as significantly higher than functional competencies, and competencies improved significantly with training. Results of the current study provide clarity about the utility of the PEF and inform our understanding of practicum-level competencies.
Development of a Natural Fiber Mat Plywood Composite
Natural fibers like kenaf, hemp, flax and sisal fiber are becoming alternatives to conventional petroleum fibers for many applications. One such applications is the use of Non-woven bio-fiber mats in the automobile and construction industries. Non-woven hemp fiber mats were used to manufacture plywood in order to optimize the plywood structure. Hemp fiber mats possess strong mechanical properties that comparable to synthetic fibers which include tensile strength and tensile modulus. This study focuses on the use of hemp fiber mat as a core layer in plywood sandwich composite. The optimization of fiber mat plywood was done by performing a three factor experiment. The three factors selected for this experiment were number of hemp mat layers in the core, mat treatment of the hemp mat, and the glue content in the core. From the analysis of all treatments it was determined that single hemp mat had the highest effect on improving the properties of the plywood structure.
Community of Inquiry Meets Critical Discourse Analysis (CDA): A CDA of Asynchronous Computer-Conference Discourse with Seminary Students in India
The purpose of this study was to better understand student learning in asynchronous computer-conference discourse (ASD) for non-native speakers of English in India through the Community of Inquiry (COI) framework. The study looked at ASD from an online course taught in the fall of 2015 to 25 students in a seminary in South India. All but one of the students were non-native speakers of English. The class consisted of 22 men and 3 women. Eight students spoke languages from the Dravidian family of languages (Malayalam, Tamil, Telegu and Kannada). Eight students were from the Northeastern states of Manipur, Nagaland and Tripura, where most languages are from the Sino-Tibetan family. Three students were native speakers of Indo-Aryan languages (Odiya and Assamese). Five students were from Myanmar representing several Sino-Tibetan languages. The COI is a framework used to understand learning in ASD, often used in online learning. To study the ASD of this group, critical discourse analysis (CDA) was used with the COI to capture the unique socio-cultural and linguistic conditions of this group. The study revealed that non-native speakers of English often reach the Exploration phase of learning but rarely show evidence of reaching the Resolution phase. This phenomenon was also observed in native English speakers as reported in the literature. Also, the structure of ASD showed that students took an examination approach to discussion shaped in part by their epistemology. This examination approach shaped how knowledge was constructed. CDA also showed that the discourse acquired an instructor-centered structure in which Resolution and Repair were initiated and finalized by the instructor. The study advances the COI framework by undergirding it with a theory of asynchronous discourse using critical discourse analysis and capturing cognitive, social and teaching presence phenomena for non-native speakers that were not observed through the traditional COI framework. These ...
A Case Study of Mathematics Teachers' Use of Short-Cycle Formative Assessment Strategies
A single case study was used to examine two middle grades mathematics teachers' use of short-cycle formative assessment strategies. Data was collected using multiple sources to provide a description of this single case. Participant change in knowledge of short-cycle formative assessment strategies was collected and analyzed through participant pre- and post-interviews and targeted instructional support was provided through professional development sessions designed to meet diverse needs of participants. Participant change in use of short-cycle formative assessment strategies was collected and analyzed through classroom observations using Assess Today observation protocol and targeted instructional support was provided through post-observation conferences with written feedback. Findings from the study verified that changes in teachers' use of short-cycle formative assessment strategies were positively influenced by the targeted instructional support provided to each participant during the study. The study further indicated that an assessment of teacher's present knowledge and use of short-cycle formative assessment strategies should be considered before providing targeted instructional support to maximize the learning potential for each teacher. Future research is needed regarding the importance of building student self-efficacy through teacher use of short-cycle formative assessment, as well as the importance of involving students in the formative assessment process.
A Woman's Place is at Work: The Rise of Women's Paid Labor in Five Texas Cities, 1900-1940
This thesis is a quantitative analysis of women working for pay aged sixteen and older in five mid-size Texas cities from 1900 to 1940. It examines wage-earning women primarily in terms of race, age, marital status, and occupation at each census year and how those key factors changed over time. This study investigates what, if any, trends occurred in the types of occupations open to women and the roles of race, age, and marital status in women working for pay in the first forty years of the 20th century.
Best Practices in Targeted Advertising for Fashion Entrepreneurs
A key to a business's success is reaching the target market. This ensures that consumers are exposed to the retailer's offerings and by turn, inspired to purchase. In turn, the business can reach its goal of a profitable organization. The purpose of this paper was to determine the most effective fashion advertising appeals for reaching target markets. To address these issues, this thesis consisted of two studies. The purpose of the first study was to determine the advice given to fashion entrepreneurs regarding effective target market practices. The purpose of the second study was to determine effective advertising strategies fashion entrepreneurs may employ for effectively reaching target markets. Data was collected to test the effectiveness of the advice from Study 1, degrees of brand awareness, attitudes towards advertising, willingness to follow trends, purchase intention, purchase behavior, and shopping involvement. The Theory of Reasoned Action was employed as the theoretical framework of the study. The framework was utilized to predict that attitudes towards targeted advertising and pressure to follow fashion trends would positively relate to intent to purchase which, in turn, would positively relate to purchase behavior. The results of this paper concluded the TRA model provided a proper framework to predict purchase behavior from targeted advertising employed by fashion entrepreneurs.
Investigation of Immersion Cooled ARM-Based Computer Clusters for Low-Cost, High-Performance Computing
This study aimed to investigate performance of ARM-based computer clusters using two-phase immersion cooling approach, and demonstrate its potential benefits over the air-based natural and forced convection approaches. ARM-based clusters were created using Raspberry Pi model 2 and 3, a commodity-level, single-board computer. Immersion cooling mode utilized two types of dielectric liquids, HFE-7000 and HFE-7100. Experiments involved running benchmarking tests Sysbench high performance linpack (HPL), and the combination of both in order to quantify the key parameters of device junction temperature, frequency, execution time, computing performance, and energy consumption. Results indicated that the device core temperature has direct effects on the computing performance and energy consumption. In the reference, natural convection cooling mode, as the temperature raised, the cluster started to decease its operating frequency to save the internal cores from damage. This resulted in decline of computing performance and increase of execution time, further leading to increase of energy consumption. In more extreme cases, performance of the cluster dropped by 4X, while the energy consumption increased by 220%. This study therefore demonstrated that two-phase immersion cooling method with its near-isothermal, high heat transfer capability would enable fast, energy efficient, and reliable operation, particularly benefiting high performance computing applications where conventional air-based cooling methods would fail.
Are Streams Protected? Outcomes of Environmental Regulation
Urban areas experience the loss of natural stream channels through conversion to artificial conveyances. This process tends to target headwater and other low order streams. The purpose of this study is to determine the patterns of stream loss in Denton, Texas, and explore the regulatory structure that manages these streams. Historic and current maps and stream data are used to map Denton's streams and categorize them according to their vertical connectivity as: 1) "intact", streams that are open to the atmosphere and connect to groundwater; 2) "concrete", channelized streams open to the atmosphere but cut off from groundwater; and 3) "buried", streams disconnected from the atmosphere and groundwater. A review of federal, state, and local regulatory codes and interviews with local government officials and other stakeholders elucidates stream management in Denton. Results from these analyses reveal high rates of stream loss in the urban center with low rates overall. The federal Clean Water Act and the local Environmentally Sensitive Areas code serve as the primary protective measures for natural streams. These regulations discourage stream impacts through expensive and complex permitting requirements. However the policies allow minor impacts which may cause cumulative effects. This study aims to inform future policy-making decisions and contribute to the knowledge of the environmental regulation of streams.
Predictors of Postsecondary Success: An Analysis of First Year College Remediation
This study was a quantitative multiple regression investigation into the relationships between campus factors of high school students graduating in 2013 who immediately enrolled in first-year college freshman level remedial coursework at a large, Central Texas two-year postsecondary institution. The goal of this study was to determine which high school campus-level factors predicted enrollment into college remedial education coursework. The dependent variable was a continuous variable representing the percentage of students from Texas public high school campuses enrolled into at least one student credit hour of remedial education during their first semester as a first-year college student. Eight high school campus-level independent variables were included in the regression model at the campus-level: at risk percentage, economically disadvantaged percentage, limited English proficient percentage, advanced course/dual-enrollment percentage, college ready math percentage, college ready English percentage, ACT average, and SAT average. Pearson correlations and linear regression results were examined and interpreted to determine the level of relationship between the eight selected variables and first-year college student remedial coursework. The multiple regression model successfully explained 26.3% (F(8,286) = 12.74. p < 0.05, r2 = 0.263) of the variance between first-year college students enrolled into remedial coursework at a large, Central Texas two-year postsecondary institution and the campus-level variables from high schools from which they graduated and indicated campus-level economic disadvantaged percentage and campus-level SAT average to be statistically significant at the p < 0.05 level.
A Mixed Methods Approach to Exploring Social Support and Resilience in Coping with Stigma and Psychological Distress among HIV-Positive Adults
Since its emergence in the U.S., HIV has been a stigmatized illness. People living with HIV (PLH) are a minority and prone to psychological distress and poor mental health outcomes due to HIV-related stigma. PLH who identify with another minority group in addition to being HIV-positive (e.g., gay, African-American) experience multiple forms of oppression or layered stigma. Affirmative social support and resilience are negatively associated with HIV-stigma and are important coping resources for PLH. We used an explanatory sequential mixed methods design study involving a quantitative survey phase and a qualitative interview phase. We explored whether social support and resilience (Positive Psychological Resources) mediate or moderate the relationship between HIV Stigma and Psychological Distress among HIV-positive adults using partial least squares (PLS) path modeling and multiple regressions. Via PLS, we found Positive Psychological Resources partially mediated the relationship between HIV Stigma and Psychological Distress: the path between HIV Stigma and Psychological distress reduced (from t = 5.49, p = .000 to t = 2.39, p = .000) but remained statistically significant. Similarly, via regression, the Sobel test was significant (Sobel = .26, SE = .07, z = 3.63, p = .000). However, moderation was not found (HIV Stigma x Positive Psychological Resources β = .05, t = .66, p = .508). Overall, our quantitative survey and qualitative interview data were consistent. We anticipate that our findings will inform strengths-based therapeutic interventions to mitigate stress and stigma among PLH.
Social Support as a Moderator of Racial/Ethnic Differences in Subclinical Atherosclerosis: The North Texas Heart Study
This study examined racial/ethnic differences in pre-clinical disease, social support, and tested whether social support was a moderator of racial/ethnic differences in subclinical atherosclerosis. Participants were NHWs, NHBs, and Latinos (n = 283) from the baseline and cross-sectional sample of the North Texas Heart Study. Results from unadjusted models showed no significant racial/ethnic differences for common or bifurcation intima-media thickness (cIMT). However, unadjusted models for cIMT showed a main effect for race/ethnicity F(2, 229) = 3.12, p = .046, partial η2 = .027, with Latinos demonstrating significantly greater internal cIMT compared to NHB but not NHWs. In minimally adjusted models, there was a main effect for race/ethnicity, F(2, 227) = 3.10, p = .047, partial η2 = .027, with significantly greater internal cIMT in Latinos compared to NHBs but not NHWs. In fully adjusted models, racial/ethnic differences in cIMT were attenuated. Contrary to study hypotheses, no racial/ethnic differences in social support were found and social support was not a moderator of racial/ethnic differences in subclinical disease. In the North Texas Heart Study, few racial/ethnic differences emerged, with fully adjusted risk factor models accounting for these differences.
Laser Additive Manufacturing of Magnetic Materials
A matrix of variably processed Fe-30at%Ni was deposited with variations in laser travel speeds as well and laser powers. A complete shift in phase stability occurred as a function of varying laser travel speed. At slow travel speeds, the microstructure was dominated by a columnar fcc phase. Intermediate travel speeds yielded a mixed microstructure comprised of both the columnar fcc and a martensite-like bcc phase. At the fastest travel speed, the microstructure was dominated by the bcc phase. This shift in phase stability subsequently affected the magnetic properties, specifically saturation magnetization. Ni-Fe-Mo and Ni-Fe-V permalloys were deposited from an elemental blend of powders as well. Both systems exhibited featureless microstructures dominated by an fcc phase. Magnetic measurements yielded saturation magnetizations on par with conventionally processed permalloys, however coercivities were significantly larger; this difference is attributed to microstructural defects that occur during the additive manufacturing process.
It's All Coming Back to You: 1980s Retro Film Culture and the Masculinity of Cult
The 1980s is a formative decade in American history. America sought to reestablish itself as a global power and to reassert the dominant ideology of white, patriarchal capitalism. Likewise, media producers in the 1980s sought to reassert the dominance of the white, male, muscled body in filmic representations. The identity politics of the 1980s and the depictions of the white, muscled body once prominent in the 1980s have been the site of conservative nostalgia for a young, male-dominated, cult audience that is a subset of a larger cultural trend known as retro film culture. This thesis provides historical context behind the populist 1980s B-action films from Cannon Group, Inc that celebrate violent masculinity in filmic representations with white, male action heroes. Equally important is the revival of VHS collecting and how this 1980s-inspired subculture reinforces white, patriarchal capitalism through the cult films they valorize and their capitalistic trading practices despite their claims of oppositionality against mainstream taste and Hollywood films. Lastly, this thesis reveals how a new cycle of contemporary films primarily produced outside of Hollywood reasserts and celebrates the dominance of the white, male, muscled body in filmic representations despite a postmodern and hyperconscious exterior. Overall, I argue how these areas of nostalgia are distinct, yet not unrelated, because they reassert white, patriarchal capitalism through the revival of conservative nostalgia for the 1980s.
Investigating Human Gut Microbiome in Obesity with Machine Learning Methods
Obesity is a common disease among all ages that has threatened human health and has become a global concern. Gut microbiota can affect human metabolism and thus may modulate obesity. Certain mixes of gut microbiota can protect the host to be healthy or predispose the host to obesity. Modern next-generation sequencing technique allows accessing huge amount of genetic information underlying microbiota and thus provides new insights into the functionality of these micro-organisms and their interactions with the host. Multiple previous studies have demonstrated that the microbiome might contribute to obesity by increasing dietary energy harvest, promoting fat deposition and triggering systemic inflammation. However, these researches are either based on lab cultivation studies or basic statistical analysis. In order to further explore how gut microbiota affect obesity, this thesis utilize a series of machine learning methods to analyze large amount of metagenomics data from human gut microbiome. The publicly available HMP (Human Microbiome Project) metagenomic sequencing data, contain microbiome data for healthy adults, including overweight and obese individuals, were used for this study. HMP gut data were organized based on two different feature definitions: taxonomic information and metabolic reconstruction information. Several widely used classification algorithms: namely Naive Bayes, Random Forest, SVM and elastic net logistic regression were applied to predict healthy or obese status of the subjects based on the cross-validation accuracy. Furthermore, the corresponding feature selection algorithms were used to identify signature features in each dataset that lead to the differences between healthy and obese samples. The results showed that these algorithms perform poorly on taxonomic data than metabolic pathway data though lots of selected taxa are still supported by literature. Among all the combinations between different algorithms and data, elastic net logistic regression has the best cross-validation performance and thus becomes the best model. In this model, several important ...
Two-Phase Spray Cooling with HFC-134a and HFO-1234yf for Thermal Management of Automotive Power Electronics using Practical Enhanced Surfaces
The objective of this research was to investigate the performance of two-phase spray cooling with HFC-134a and HFO-1234yf refrigerants using practical enhanced heat transfer surfaces. Results of the study were expected to provide a quantitative spray cooling performance comparison with working fluids representing the current and next-generation mobile air conditioning refrigerants, and demonstrate the feasibility of this approach as an alternative active cooling technology for the thermal management of high heat flux power electronics (i.e., IGBTs) in electric-drive vehicles. Potential benefits of two-phase spray cooling include achieving more efficient and reliable operation, as well as compact and lightweight system design that would lead to cost reduction. The experimental work involved testing of four different enhanced boiling surfaces in comparison to a plain reference surface, using a commercial pressure-atomizing spray nozzle at a range of liquid flow rates for each refrigerant to determine the spray cooling performance with respect to heat transfer coefficient (HTC) and critical heat flux (CHF). The heater surfaces were prepared using dual-stage electroplating, brush coating, sanding, and particle blasting, all featuring "practical" room temperature processes that do not require specialized equipment. Based on the obtained results, HFC-134a provided a better heat transfer performance through higher HTC and CHF values compared to HFO-1234yf at all tested surfaces and flow rates. While majority of the tested surfaces provided comparable HTC and modestly higher CHF values compared to the reference surface, one of the enhanced surfaces offered significant heat transfer enhancement.
Crystallographic Complex Reflection Groups and the Braid Conjecture
Crystallographic complex reflection groups are generated by reflections about affine hyperplanes in complex space and stabilize a full rank lattice. These analogs of affine Weyl groups have infinite order and were classified by V.L. Popov in 1982. The classical Braid theorem (first established by E. Artin and E. Brieskorn) asserts that the Artin group of a reflection group (finite or affine Weyl) gives the fundamental group of regular orbits. In other words, the fundamental group of the space with reflecting hyperplanes removed has a presentation mimicking that of the Coxeter presentation; one need only remove relations giving generators finite order. N.V Dung used a semi-cell construction to prove the Braid theorem for affine Weyl groups. Malle conjectured that the Braid theorem holds for all crystallographic complex reflection groups after constructing Coxeter-like reflection presentations. We show how to extend Dung's ideas to crystallographic complex reflection groups and then extend the Braid theorem to some groups in the infinite family [G(r,p,n)]. The proof requires a new classification of crystallographic groups in the infinite family that fail the Steinberg theorem.
Using Possible Selves to Examine the Impact of Internalized Stigma of Mental Illness on the Career Development of College Students with Hidden Disability
The purpose of the study was to examine the impact of internalized stigma of mental illness on the career development of college students with hidden disabilities. The availability of research investigating career variables within this population is limited and is primarily focused within the vocational rehabilitation arena. Therefore, one of the goals of the current study was to link separate bodies of literature on college students with disabilities, career development, and internalized stigma of mental illness. The second goal was to examine the interaction of internalized stigma of mental illness between career decision self-efficacy and career exploration on the perceived likelihood of achieving hoped for occupational possible selves (OPS). The study included college students with hidden disabilities and investigated variables related to mental illness and career. Participants were administered a background information questionnaire, the Career Decision Self-Efficacy scale (CDSE-SF), selected subscales of the Career Exploration Survey (CES), and the Internalized Stigma of Mental Illness scale (ISMI). Contrary to hypotheses, career decision making self-efficacy, career self-exploration, and internalized stigma of mental illness did not have a direct effect on the perceived likelihood of achieving hoped for OPS. However, career environment exploration did have a direct and positive association with perceived likelihood of achieving hoped for OPS. Results further indicated internalized stigma of mental illness did not moderate the effect of career decision self-efficacy and career exploration on the perceived likelihood of achieving one's hoped for occupational self. Study implications, limitations, and future directions are discussed.
Reproduction and Metabolic Responses to Acute and Chronic Hypoxia in Ovoviviparous Blaberid Cockroaches, with a Focus on Blaptica dubia
The major components of the tracheal system of insects are an extension of the exoskeleton, and the size of the exoskeleton is fixed in the adult stage, so any increase in metabolic demand that may accompany reproduction must be met by a relatively unaltered tracheal system that the female set in place at ecdysis, when entering adulthood. Acute hypoxia tends to elicit an increase in ventilation in insects, and here, I observe increased interburst VCO2 release, and a tendency towards a more continuous gas exchange pattern being preferred over discontinuous gas exchange when Blaptica dubia and Eublaberus posticus are exposed to a descending regime of hypoxia. Additionally, higher temperatures appear to increase sensitivity to hypoxia in these species, an expected result because both species, like most ectothermic animals, display a Q10 effect, increasing metabolic rates as temperature increases. The reproductive mode of B. dubia is considered to be lecithotrophic pseudoviviparity (or type A ovoviviparity), and by the time the embryos are born, they have more than doubles in volume from the time of oviposition. This gain is apparent in the wet mass of the embryo, with no change occurring in dry mass. The egg mass that can be attributed to water begins at 39% at oviposition and increased to nearly 82% at hatching. The metabolic rates of females and embryos increase as embryonic development progresses, but bomb calorimetry reveals that energy content of the embryos does not change. It is possible that these embryos gain some nutrition from the mother during embryonic development, but direct evidence remains to be demonstrated. Blaptica dubia and Eublaberus posticusare both blaberid species that display the same reproductive mode, pseudoviviparity, with incubation occurring in a brood sac. Comparisons between the reproductive traits of B. dubia and E. posticus reveal that the two species have similar ...
The Impact of Observational Learning on Physical Activity Appraisal and Exertion Following Experimental Back Injury and the Role of Pain-Related Fear
Chronic low back pain (CLBP) is one of the most prevalent and disabling health conditions in the US and worldwide. Biomedical explanations of acute injury fail to account for why some individuals experience remission of pain and restoration of physical function while others do not. Pain-related fear, accompanied by elevated appraisals of physical exertion and avoidance of physical activity, has emerged as a central psychosocial risk factor for transition from acute injury to chronic pain and disability. Research has indicated that these pain-related factors may be maintained through observational learning mechanisms. To date, no studies have experimentally examined the role of observational learning and pain-related fear in the context of actual musculoskeletal injury. Accordingly, the present study examined the impact of observational learning and pain-related fear on activity appraisals and exertion following experimentally- induced acute low back injury. Healthy participants' appraisal of standardized movement tasks along with measures of physical exertion were collected prior to and following a procedure designed to induce delayed onset muscle soreness (DOMS) to the lower back. Following induction of DOMS, participants observed a video prime depicting CLBP patients exhibiting either high or low pain behavior during similar standardized movements. In line with hypothesized effects, participants assigned to the high pain behavior prime demonstrated greater elevation in pain and harm appraisals as well as greater decrement in physical exertion. Further in line with hypotheses, significant changes in appraisal and physical performance following the high pain behavior prime were only observed among participants endorsing high pain-related fear during baseline assessment. Discussion of findings addresses potential mechanisms of action as well as study limitations and direction for future research.
A Convergence of LDPC Based on Eigenvalues
Low-density parity check (LDPC) codes are very popular among error correction codes because of their high-performance capacity. Numerous investigations have been carried out to analyze the performance and simplify the implementation of LDPC codes. Relatively slow convergence of iterative decoding algorithm affects the performance of LDPC codes. Faster convergence can be achieved by reducing the number of iterations during the decoding process. In this thesis, a new approach for faster convergence is suggested by choosing a systematic parity check matrix that yields lowest Second Smallest Eigenvalue Modulus (SSEM) of its corresponding Laplacian matrix. MATLAB simulations are used to study the impact of eigenvalues on the number of iterations of the LDPC decoder. It is found that for a given (n, k) LDPC code, a parity check matrix with lowest SSEM converges quickly as compared to the parity check matrix with high SSEM. In other words, a densely connected graph that represents the parity check matrix takes more iterations to converge than a sparsely connected graph.
Fabrication of Photonic Crystal Templates through Holographic Lithography and Study of their Optical and Plasmonic Properties in Aluminium Doped Zinc Oxide
This dissertation focuses on two aspects of integrating near-infrared plasmonics with electronics with the intent of developing the platform for future photonics. The first aspect focuses on fabrication by introducing and developing a simple, single reflective optical element capable of high–throughput, large scale fabrication of micro- and nano-sized structure templates using holographic lithography. This reflective optical element is then utilized to show proof of concept in fabricating three dimensional structures in negative photoresists as well as tuning subwavelength features in two dimensional compound lattices for the fabrication of dimer and trimer antenna templates. The second aspect focuses on the study of aluminum zinc oxide (AZO), which belongs to recently popularized material class of transparent conducting oxides, capable of tunable plasmonic capabilities in the near-IR regime. Holographic lithography is used to pattern an AZO film with a square lattice array that are shown to form standing wave resonances at the interface of the AZO and the substrate. To demonstrate device level integration the final experiment utilizes AZO patterned gratings and measures the variation of diffraction efficiency as a negative bias is applied to change the AZO optical properties. Additionally efforts to understand the behavior of these structures through optical measurements is complemented with finite difference time domain simulations.
John Playford's "The Division Violin": Improvisation and Variation Practice in English Violin Music of the Seventeenth Century
English publisher John Playford (1623-1686/1687) first published his "The Division Violin: Containing a Collection of Divisions Upon Several Grounds for the Treble-Violin" in 1684. The first edition of this violin collection contains 26 written-out examples of improvisation, serving as a living snapshot of the performance practice of the time. This research is based on the second edition, which Playford had expanded into 30 pieces for the violin, published in 1685. The purpose of this study is to investigate the art of improvisation in England during the late 17th century, focusing on Playford's "The Division Violin." The dissertation first surveys the development of English violin music in the 17th century. Then, the dissertation traces eight selected 16th-century Italian diminution manuals. This will help readers understand the progression of the Italian diminution and improvisation practice in the 16th century and how it relates to the English division of the 17th century. Finally, based on a thorough research of the 17th-century improvisatory style and rhetorical approach, the author of this study provides performance suggestions on "Mr. Farinell's Ground," No. 5 from "The Division Violin."
A Comprehensive Performance Guide for the Use of Advanced Technology in Euphonium Repertoire with Electronic Media through Analyses of Works by D. Edward Davis, Neal Corwell, and Lucy Pankhurst
Solos for euphonium with electronic media present the unique challenge of incorporating an active, physical involvement in the live accompaniment through sound-altering technology such as guitar pedals or digital processors. Instructions for this solo genre are often vague and demand a general knowledge of how to use non-traditional devices. Due to the lack of information available on newly-composed pieces for this medium, students and professionals easily overlook the artistic merit of electroacoustic music. This dissertation provides a comprehensive performance guide that aids in the set-up and operation of advanced technology and presents a methodical approach to performing common musical and technical challenges found in modern euphonium repertoire with electronic media. Included in this dissertation are tables of common audio vocabulary and images of connectors, safety precautions, equipment recommendations with performance settings, a list of required connectors, adapters, cables, speakers, and amplifiers, performance set up diagrams, background information, and analyses of both the technical and musical aspects of each piece. In the appendices are signal flow charts, visual illustrations of polar recording patterns, and an updated catalog of published and unpublished original, adapted, and arranged euphonium solos with live electronics and electronic media accompaniment between 1970 and 2017.
Neurocognitive Effects of Gist Reasoning Training in Student-Athletes with Concussions, ADHD, and Learning Disabilities
Concussions, attention-deficit disorder (ADHD), and learning disabilities can adversely impact learning and academic achievement, particularly with respect to attention, memory, and executive functioning; fortunately, cognitive training can be beneficial and remediating these weaknesses. One such program, strategic memory advanced reasoning training (SMART), utilizes a top-down approach to train individuals in executive, higher-ordered thinking strategies including strategic attention, integration, and innovation to facilitate information synthesis and enhance cognitive efficiency. Thus, the purpose of the study is to examine whether SMART improved performances on various neuropsychological measures tapping into attention, processing speed, memory, and executive functioning for college student-athletes with neurological conditions (e.g., concussions, ADHD, LD). Student-athletes were randomly assigned to the SMART program or a "wait-list" control group and were administered a neuropsychological battery at baseline, immediately following the intervention, and after a four-month delay. Results showed that participants benefited from SMART with respect to working memory immediately following the intervention after controlling for baseline scores. The benefits of working memory also persisted after four months. Additionally, SMART was beneficial for improving attention, but only after four months after the intervention. The findings of the current study were consistent with previous studies which showed positive effects of SMART on working memory with a variety of populations (e.g., children, adolescents, older adults, Veterans, brain-injured patients); however, the current study did not see improved performance on other aspects of executive functioning which contradict prior research. Statistical differences between the present study and prior research regarding SMART may be explained in methodology, participant characteristics, research setting, and/or limitations. Future studies may include combining cognitive training as the intervention and utilizing neuroimaging alongside cognitive training to examine the relationship between structural/functional change with neuropsychological performance.
An Investigation of the Impact of Social Vulnerability Research on the Practice of Emergency Management
This dissertation examines the extent to which social vulnerability, as studied by researchers across multiple disciplines, has influenced the practice of emergency management at the local level. This study addresses two major research questions to accomplish this goal. First, how do local emergency managers perceive and define social vulnerability? Second, what strategies do local emergency managers employ to reach and meet the needs of socially vulnerable populations? Semi-structured interviews were conducted in person or by phone with a sample of local emergency managers, city managers, and American Red Cross personnel from the Houston - Galveston and the South East Texas regions as defined by the respective Councils of Government. A modified grounded theory approach was used with a constant comparative method to identify themes for each research question. Triangulation was accomplished through secondary census data and supplemental interviews. The interview data reveal that social vulnerability research has had an indirect influence on the practice of emergency management at the local level. This influence is facilitated through state and federal policy, training, and plans development. Based on the interview data, four themes were identified that capture the various ways in which local emergency management officials perceive and define social vulnerability. These include vulnerability as poverty and culture, vulnerability as a lack of security, vulnerability as a moral imperative, and vulnerability as a lack of awareness and knowledge. In terms of strategies employed to address social vulnerability, the data suggest four themes: leaving it to the professionals, bringing in volunteers, leveraging protocols to build buy-in, and fostering flexibility. The findings reveal the importance in closing the knowledge gap between research and practice, because increased damage, harm, and death can occur when the social inequalities of everyday life are not addressed in the planning process by emergency managers. The findings also reveal that ...
Formation Control of Multi-Agent Systems
Formation control is a classical problem and has been a prime topic of interest among the scientific community in the past few years. Although a vast amount of literature exists in this field, there are still many open questions that require an in-depth understanding and a new perspective. This thesis contributes towards exploring the wide dimensions of formation control and implementing a formation control scheme for a group of multi-agent systems. These systems are autonomous in nature and are represented by double integrated dynamics. It is assumed that the agents are connected in an undirected graph and use a leader-follower architecture to reach formation when the leading agent is given a velocity that is piecewise constant. A MATLAB code is written for the implementation of formation and the consensus-based control laws are verified. Understanding the effects on formation due to a fixed formation geometry is also observed and reported. Also, a link that describes the functional similarity between desired formation geometry and the Laplacian matrix has been observed. The use of Laplacian matrix in stability analysis of the formation is of special interest.
Neurological Responses to a Glucose Diet in Caenorhabditis elegans
TRPV channels play a role in both mammalian insulin signaling, with TRPV1 expression in pancreatic beta-cells, and in C. elegans insulin-like signaling through expression of OSM-9, OCR-1, and OCR-2 in stress response pathways. In response to a glucose-supplemented diet, C. elegans are know to have sensitivity to anoxic stress, exhibit chemotaxis attraction, and display reduced egg-laying rate. Transcriptome analysis reveals that glucose stimulates nervous system activity with increased transcript levels of genes regulating neurotransmitters. Ciliated sensory neurons are needed for a reduced egg-laying phenotype on a glucose-supplemented diet. Egg-laying rate is not affected when worms graze on glucose-supplemented Delta-PTS OP50 E. coli, which is defective in glucose uptake. This suggests a possible sensory neuron obstruction by exopolysaccharides produced by standard OP50 E. coli on glucose, eliciting a starvation response from the worm and causing reduced egg-laying rate. Glucose chemotaxis is affected in specific TRPV subunit allele mutants: ocr-2(vs29) and osm-9(yz6), serotonin receptor mutants: ser-1(ok345) and mod-1(ok103), and G-alpha protein mutant: gpa-10(pk362). TRPV deletion mutants had no effect on glucose chemotaxis, alluding to the modality role pf TRPV alleles in specific sensory neurons. The role of serotonin in a reduced egg-laying rate with glucose remains unclear.
"Among the Voices Voiceless": Setting the Words of Samuel Beckett
Among the Voices Voiceless is a composition for flute (doubling piccolo), clarinet (doubling bass clarinet), viola, cello, percussion, piano, and electronics, based on the poem "What would I do without this world faceless incurious" by Samuel Beckett. The piece is a setting for disembodied voice: the vocal part exists solely in the electronics. Having no physical body, the voice is obscured as the point of empathy for the audience. In addition, instrumental solos compete for focus during the work's twenty minute duration. In passages including a soloist, the soloist functions simultaneously as antagonist and avatar to the disembodied voice. Spoken word recordings and electronic manipulation of instrumental material provides further layers of ambiguity. The companion critical essay "Among the Voices Voiceless": Setting the Words of Samuel Beckett proposes the distillation of Beckett's style into the elements of prosaicness, repetition, fragmentation, ambiguity, and symmetry. Discussions of Beckett's works such as Waiting for Godot and Molloy demonstrate these elements in his practice. This framework informs the examination of two other musical settings of Beckett's poetry: Neither by Morton Feldman and Odyssey by Roger Reynolds. Finally, these elements are used to analyze and elucidate the compositional decisions made in Among the Voices Voiceless.
Comparison of the "Méthode Pour La Guitare" by Fernando Sor with the "Méthode Complète Pour La Guitare Par Ferdinand Sor, Rédigée Et Augmentée De Nombreux Exemples Et Leçons Suivis D'une Notice Sur La 7e Corde" by Napoléon Coste
The nineteenth century presents a great increase in publications of guitar methods. Most authors of the time published several versions of their works. Fernando Sor, perhaps the most prominent guitar composers of the time—whose Méthode is regarded today as the most important of the period—only published one edition. However, Napoleon Coste took on the task to do a second account. The literature reviewed shows substantial existing information regarding background, type of text, tone, and contents of Sor's work, but comparisons to date are not substantial. Therefore, there is a need to compare these two texts side by side to yield a complete view of their pairing. The existing negative views of Coste's edition hinder the importance of Coste's work as reference to Segovia's publication of Sor studies, and as a clearer pedagogical application of many of Sor's concepts which are sidetracked by his response to criticism and his elaborations in matters beyond his main subject matter. I provide a comprehensive review of Sor's method, an outline and a consideration of his concepts. Then I offer a complete English translation of Coste's method which is inexistent until now. The comparison follows pointing at differences and similarities. Results show that Coste clarifies and complements many of the principles in less text and simpler language. He modifies certain others either to approach Sor's practice or to depart to a newer standard. He offers his own lessons and sections to apply Sor's concepts. Coste's text heads towards a pedagogical synthesis of Sor's method, but it is incomplete because he omits some concepts without leading the readers to consult Sor. Coste's pedagogical and practical relevance is fundamental for modern standard techniques.
Music With and Without Lyrics Increases Motivation, Affect, and Arousal during Moderate-Intensity Cycling
Music is used to distract, energize, and entertain during exercise by producing positive psychological and physiological responses. Specifically, listening to music during exercise enhances performance, increases motivation, improves affect, and optimizes arousal. Researchers have identified several elements of music that may moderate this relationship, including lyrics. However, few studies to date have examined the influence of motivational lyrics on psychological and physiological states during exercise. Thus, the primary purpose was to investigate the effects of lyrics in music on motivation, affect, arousal, and perceived exertion during moderate intensity cycling. Thirty (Mage = 21.0 ± 2.9 years old) college-aged individuals performed three, 8-min acute bouts of moderate-intensity exercise on a cycle ergometer during music with lyrics (ML), music without lyrics (MNL), and no music control (MC) conditions. Measures of motivation, affect, arousal, and perceived exertion were taken before and after a 6-min warm-up, every 2-min during the exercise bout, and following a 2-min cool-down. For ML and MNL conditions, participants reported higher motivation, affect, and arousal during exercise relative to the MC condition. As expected, RPE increased throughout the exercise period, with no condition differences observed. Additionally, there were no differences in responses between the ML and MNL conditions. Collectively, these results suggest that music, regardless of lyrical content, can enhance psychological responses during exercise. The current findings may help address common exercise barriers and inform exercise practitioners on music selection to improve exercise adherence.
Elections and Authoritarian Rule: Causes and Consequences of Adoption of Grassroots Elections in China
This dissertation investigates the relationship between elections and authoritarian rule with a focus on the case of China's adoption of elections at the grassroots level. In this dissertation, I look at the incentives facing Chinese local governments in choosing between holding competitive elections or state-controlled elections, and how the selection of electoral rules shapes the public's preferences over political institutions and influences the citizens' political behaviors, especially voting in elections and participation in contentious activities. The overarching theme in this dissertation proposes that the sources and consequences of Chinese local elections are conditioned on the state-owned resources and the governing costs. When the amount of state-owned resources to rule the local society is limited, the paucity of resources will incentivize authoritarian governments to liberalize grassroots elections to offset the governance costs. The various levels of election liberalization will lead to different consequences in the public's political behavior. An abundance of state-owned resources not only discourages rulers from sharing power with the local society, but also supplies the rulers with strong capacity to obtain loyalty from voters when elections are adopted. As a result, elections under authoritarian governments with an abundance of state-owned resources will see more loyalist voters than elections with authoritarian governments with fewer state-owned resources. In addition, the varieties of election practices will exert impacts on public opinion toward the authoritarian government: awareness of elections will enhance public trust in the government and decrease the public's intention to challenge the incumbents' authority while at the same time increasing the public's faith in the institutions, thereby encouraging the public to adopt official channels to air their grievances. The analysis of the village-level as well as individual-level survey data and cases lends empirical supports to the argument. First, I find that the governing costs—measured by the size of labor force—are ...
Size Framing: Conceptualization and Applications in Consumer Behavior
Size information is vital in many consumer contexts, but currently, no central framework or conceptual model exists for a thorough understanding of the underlying process of how consumers interpret size information and form size judgments. Thus, the purpose of this three-paper dissertation is to introduce such a framework, discuss future research directions based on that framework, and pursue a few of these directions in the second and third papers, both of which focus on a vanity sizing context. The resulting work and findings illustrate the process through which consumers go in forming size judgments and collectively present both scholars and practitioners with a common basis for future study and implementation of findings in contexts in which size information is salient.
The Role Humor Plays in Facilitating Rapport, Engagement, and Motivation in Graduate Online Learning Environments
This study seeks to explore, using an interpretivist phenomenological approach, how humor may impact rapport, engagement, and motivation in graduate online learning environments. Through detailed qualitative analysis of semi-structured interviews, direct observation, and demographic survey data, emergent themes were identified that support the use of appropriate humor to create a positive online environment in which learning can take place. Evidence indicates that humor, when used purposefully and appropriately, is a valuable tool for promoting rapport and engagement amongst course members through community-building and enhanced interpersonal connections. The results of this study reveal the importance of finding common ground and shared experiences to improve the overall social and communicative culture of an online course. The results also support the idea that online instructors should make a great effort in connecting with students in online courses and must make a greater effort to appropriately engage in their online courses. Appropriate recommendations are made for practical application of humor to support pedagogy, as well as recommendations for future research on humor in educational environments.
Nightmare Disorder Prevalence as Defined by the DSM-5 in a College Sample
The nightmare prevalence literature to date has largely focused on nightmare episode severity (i.e. frequency), with 8%-87% of individuals reporting these events in the past week to year. While this has helped to determine the prevalence of these events, focus on the episode severity alone is problematic because it means little is known about the actual prevalence of nightmare disorder. Moreover, focus on episode severity likely overestimates the actual prevalence of clinically significant nightmares while also obscuring clinically significant consequences of the disorder. Understanding the prevalence of nightmare disorder can help guide treatment planning and interventions. The present study recruited UNT undergraduates (N = 372; 351 analyzed) and managed all participant data using Research Electronic Data Capture (REDCap). The present study aimed to determine the prevalence of nightmare disorder, as stated in the DSM-5, to facilitate accurate characterization of the disorder. Additionally, as part of the secondary aim the influence of gender on nightmare disorder status and psychological wellbeing as measured by psychological and sleep outcome variables was examined. Finally, comparisons of individuals with DSM-5-defined nightmare disorder to those without the disorder were conducted on previously examined correlates (e.g., trauma symptoms, depression).
Extended String Techniques and Special Effects in Arnold Schoenberg's String Quartet No. 1 and Its Significance in Chamber Music Literature
Arnold Schoenberg's String Quartet No. 1, Op. 7 stands out as being the first chamber music piece to use a vast number and variety of extended string techniques within one composition. This paper examines a brief history of extended string techniques in chamber music, analyses the unique ways in which Schoenberg applied extended string techniques to manipulate motives in his Op. 7 quartet, and ultimately shows that Schoenberg's use of extended string techniques influenced future composers to employ even more extended techniques and special effects in their own twentieth-century chamber music.
Trajectories of Burden and Depression in Caregivers Following Traumatic Injury: The Role of Resilience
As part of an effort to understand psychological consequences among family members of patients sustaining a traumatic injury, medical research has turned to the role of resilience – or the ability to bounce back from and maintain psychological well-being in the wake of an adverse event— in mitigating the potential distress (i.e., depression and burden) of caregiving (Bonanno, 2004; Roberson et al., under review). This study sought to examine the ability for trait-resilience to predict trajectories of distress over the course of a year among 124 family members and loved ones of patients admitted to a Level I Trauma Center. A cross-lagged path model examining resilience, burden, and depression at baseline, 3, 6, and 12 months after injury showed that, while depression strongly predicted later burden, resilience was not a significant predictor of either outcome in the model. When depression and burden were subjected to a person-centered analysis (i.e., latent growth curve analysis), two major classes were identified: caregivers with high, chronic distress (33% of the sample) and low-moderate distress that declined over time. A three-class solution for caregiver burden further identified a moderate, increasing trajectory class. Predictive discriminant analyses revealed that trait-resilience was a major differentiating trait between class membership (rs = .23 for depression; rs = .32 for burden); further, presence of PTSD symptoms at baseline, gender, and history of depression were shown to be strong factors in distinguishing class membership across both outcomes. This study helps shed insight into the well-being of caregivers in the wake of a loved one's traumatic injury, in addition to possible identifying risk factors while patients are still admitted in the ICU. Lastly, the study provides alternatives for analyses that focus on longitudinal outcomes, particularly person- vs. variable-centered solutions.
Developing a Phylogeny Based Machine Learning Algorithm for Metagenomics
Metagenomics is the study of the totality of the complete genetic elements discovered from a defined environment. Different from traditional microbiology study, which only analyzes a small percent of microbes that could survive in laboratory, metagenomics allows researchers to get entire genetic information from all the samples in the communities. So metagenomics enables understanding of the target environments and the hidden relationships between bacteria and diseases. In order to efficiently analyze the metagenomics data, cutting-edge technologies for analyzing the relationships among microbes and communities are required. To overcome the challenges brought by rapid growth in metagenomics datasets, advances in novel methodologies for interpreting metagenomics data are clearly needed. The first two chapters of this dissertation summarize and compare the widely-used methods in metagenomics and integrate these methods into pipelines. Properly analyzing metagenomics data requires a variety of bioinformatcis and statistical approaches to deal with different situations. The raw reads from sequencing centers need to be processed and denoised by several steps and then be further interpreted by ecological and statistical analysis. So understanding these algorithms and combining different approaches could potentially reduce the influence of noises and biases at different steps. And an efficient and accurate pipeline is important to robustly decipher the differences and functionality of bacteria in communities. Traditional statistical analysis and machine learning algorithms have their limitations on analyzing metagenomics data. Thus, rest three chapters describe a new phylogeny based machine learning and feature selection algorithm to overcome these problems. The new method outperforms traditional algorithms and can provide more robust candidate microbes for further analysis. With the frowing sample size, deep neural network could potentially describe more complicated characteristic of data and thus improve model accuracy. So a deep learning framework is designed on top of the shallow learning algorithm stated above in order to further ...
A Classification of the Homogeneity of Countable Products of Subsets of Real Numbers
Spaces such as the closed interval [0, 1] do not have the property of being homogeneous, strongly locally homogeneous (SLH) or countable dense homogeneous (CDH), but the Hilbert cube has all three properties. We investigate subsets X of real numbers to determine when their countable product is homogeneous, SLH, or CDH. We give necessary and sufficient conditions for the product to be homogeneous. We also prove that the product is SLH if and only if X is zero-dimensional or an interval. And finally we show that for a Borel subset X of real numbers the product is CDH iff X is a G-delta zero-dimensional set or an interval.
Developing Precipitation Hardenable High Entropy Alloys
High entropy alloys (HEAs) is a concept wherein alloys are constructed with five or more elements mixed in equal proportions; these are also known as multi-principle elements (MPEs) or complex concentrated alloys (CCAs). This PhD thesis dissertation presents research conducted to develop precipitation-hardenable high entropy alloys using a much-studied fcc-based equi-atomic quaternary alloy (CoCrFeNi). Minor additions of aluminium make the alloy amenable for precipitating ordered intermetallic phases in an fcc matrix. Aluminum also affects grain growth kinetics and Hall-Petch hardenability. The use of a combinatorial approach for assessing composition-microstructure-property relationships in high entropy alloys, or more broadly in complex concentrated alloys; using laser deposited compositionally graded AlxCrCuFeNi2 (0 < x < 1.5) complex concentrated alloys as a candidate system. The composition gradient has been achieved from CrCuFeNi2 to Al1.5CrCuFeNi2 over a length of ~25 mm, deposited using the laser engineered net shaping process from a blend of elemental powders. With increasing Al content, there was a gradual change from an fcc-based microstructure (including the ordered L12 phase) to a bcc-based microstructure (including the ordered B2 phase), accompanied with a progressive increase in microhardness. Based on this combinatorial assessment, two promising fcc-based precipitation strengthened systems have been identified; Al0.3CuCrFeNi2 and Al0.3CoCrFeNi, and both compositions were subsequently thermo-mechanically processed via conventional techniques. The phase stability and mechanical properties of these alloys have been investigated and will be presented. Additionally, the activation energy for grain growth as a function of Al content in these complex alloys has also been investigated. Change in fcc grain growth kinetic was studied as a function of aluminum; the apparent activation energy for grain growth increases by about three times going from Al0.1CoCrFeNi (3% Al (at%)) to Al0.3CoCrFeNi. (7% Al (at%)). Furthermore, Al addition leads to the precipitation of highly refined ordered L12 (γ′) and B2 precipitates in ...
The Influence of Chinese Instruments on the Violin: A Practice Guide of Three Violin Techniques
Contemporary professional violinists face constant exposure to multicultural compositions. For best results, they should be able to understand, capture, and express the subtleties of different styles. The violin and its repertoire spread to China through European missionaries during the late seventeenth century and continued to be developed by Chinese scientists and musicians who studied abroad. During the twentieth and twenty-first centuries, Chinese composers wrote many violin pieces inspired by the unique sounds of Chinese instruments. Additionally, Chinese music scholars wrote numerous essays to discuss the new Chinese style. However, much of this research has been focused on the composers and the structures of the compositions rather than on the details of violin techniques necessary to play the repertoire. The techniques in Chinese violin compositions are unique and are influenced by the traditional instruments including string, wind, and percussion instruments. Furthermore, the style of such compositions is affected by the elements of Chinese culture, such as the language, the elite society and its poetic tradition, and historical legends and events. This dissertation provides examples of Chinese violin repertoire which demonstrate the principles of three main violin techniques in the Chinese style: slides, chords, and pizzicati. In order to help professional violinists better perform Chinese violin compositions, the dissertation also includes a number of exercises covering each technique above.
Dynamic Screening via Intense Laser Radiation and Its Effects on Bulk and Surface Plasma Dispersion Relations
Recent experimentation with excitation of surface plasmons on a gold film in the Kretschmann configuration have shown what appears to be a superconductive effect. Researchers claimed to see the existence of electron pairing during scattering as well as magnetic field repulsion while twisting the polarization of the laser. In an attempt to explain this, they pointed to a combination of electron-electron scattering in external fields as well as dynamic screening via intense laser radiation. This paper expands upon the latter, taking a look at the properties of a dynamic polarization function, its effects on bulk and surface plasmon dispersion relations, and its various consequences.
The Role of Self-Compassion in Posttraumatic Growth
Although the experience of trauma is associated with a great deal of psychological distress, it may also lead to meaningful positive change, known as posttraumatic growth (PTG), evidenced as progression in areas of life appreciation, intimacy in relationships, sense of personal strength, new possibilities, and spiritual development. Utilizing an acceptance and commitment therapy (ACT) perspective, the current study explored whether self-compassion helped to explain the willingness to approach and make sense of a trauma, leading to growth. A sample of 758 undergraduate students completed online self-report questionnaires, and results suggested that self-compassion does partially predict PTG and support for how self-compassion may be understood in relation to PTG is provided. Implications of the current study's findings, as well as suggestions for future research related to trauma within a college population, are discussed.
Mobile Learning in a Mobile World: Understanding the Views of Parents with Mobile Technology in the Singaporean Elementary Classroom
Personal handheld mobile technology represents a growing topic of interest for K-12 educators. Devices such as iPads, tablets, and smartphones, in particular, are becoming more ubiquitous in society and prevalent in classrooms of children of all ages. The ease of access, combined with growing functionality and capacity of these devices creates opportunities that were previously unimaginable. Professional educators are beginning to recognize the value such devices offer for enriching and expanding opportunities for learning both inside and outside of the classroom. The views of educators and students regarding mobile technology have been well documented in existing literature. What is less clear is how parents view personal mobile technology when applied to formal and informal learning opportunities. Using quantitative analysis, this study examines the views of parents when mobile technology is utilized in Singaporean third grade classrooms. This study represents a pioneering effort to better understand the evolving role of parents and serves as a foundation for future research to explore the role of parents as partners when personal mobile technology is used for learning. The constructs identified in this study reveal that parents do believe technology skills are important in the modern age of learning and working.
Numerical Values of the Hausdorff and Packing Measures for Limit Sets of Iterated Function Systems
In the context of fractal geometry, the natural extension of volume in Euclidean space is given by Hausdorff and packing measures. These measures arise naturally in the context of iterated function systems (IFS). For example, if the IFS is finite and conformal, then the Hausdorff and packing dimensions of the limit sets agree and the corresponding Hausdorff and packing measures are positive and finite. Moreover, the map which takes the IFS to its dimension is continuous. Developing on previous work, we show that the map which takes a finite conformal IFS to the numerical value of its packing measure is continuous. In the context of self-similar sets, we introduce the super separation condition. We then combine this condition with known density theorems to get a better handle on finding balls of maximum density. This allows us to extend the work of others and give exact formulas for the numerical value of packing measure for classes of Cantor sets, Sierpinski N-gons, and Sierpinski simplexes.
What are the Experiences of African American Female Principals in High-Poverty Urban Schools?
The purpose of this study was to explore the experiences of African American female principals serving in high-poverty urban schools. This study was warranted due to the growing number of African American female principal leaders in urban schools over the last 20 years. School leaders in urban school districts are expected to increase academic achievement, support district initiatives, and foster the development of urban communities. The study results will serve as a source of information to educators on similar journeys.